1. Field
The present invention relates to methods and apparatuses for sending and receiving digital broadcasting content to provide two-dimensional (2D) or three-dimensional (3D) content.
2. Description of Related Art
Digital broadcast transport systems may provide a caption service for generating captions to be displayed on a video screen while providing video content and audio content via a broadcast program. Digital broadcast receiving systems may reproduce a video screen on which captions are displayed by decoding received video data to reconstruct video content and combining the captions generated by using caption data received via the caption service.
Requirements for 3D content accompanied by a sense of reality and a 3D effect have increased. Further, content or programs for broadcasts prepared to be reproduced in 3D have appeared. Digital broadcast receiving systems which support 3D video are able to reproduce a 3D video by receiving content for a 3D broadcast. Based on changes in methods of reproducing broadcasting content due to supply of 3D video broadcasting content, additional functions of the digital broadcast receiving systems also require changes.
SUMMARYOne or more exemplary embodiments provide a method or providing 3D caption information for realizing a 3D caption by using 2D caption data obtained from a digital broadcasting stream, thereby realizing the 3D caption by using the 3D caption information.
According to an aspect of an exemplary embodiment, there is provided a method for generating a broadcasting bitstream for a digital caption broadcast, the method including: receiving video data in which a video including at least one of a 2D video and a 3D video is encoded; determining caption data for reproduction in conjunction with the video, and 3D caption converting information including information relating to a converting speed of an offset for reproducing the caption data as a 3D caption; and outputting a bitstream for a digital broadcast by multiplexing the received video data, the determined caption data, and the determined 3D caption converting information.
The outputting the bitstream includes: inserting the caption data into at least one of a user data region of the digital broadcasting bitstream, a caption service data region, and a section table region; and inserting the 3D caption converting information into at least one of a caption service block of the bitstream, a caption window command, and the section table region.
According to an aspect of another exemplary embodiment, there is provided a method for receiving a broadcasting bitstream for a digital caption broadcast is provided, the method including: receiving a bitstream comprising encoded video data which includes at least one of a 2D video and a 3D video; extracting the encoded video data, caption data for reproduction in conjunction with a video, and 3D caption converting information comprising information relating to a converting speed of an offset for reproducing the caption data as a 3D caption from the bitstream by de-multiplexing and parsing the received bitstream; and determining a reproducing form of the caption data relating to displaying the reproduced caption data as a 3D caption on a video screen, based on the extracted 3D caption converting information.
The method may further include: reconstructing a video which includes at least one of the 2D video and the 3D video by decoding the encoded video data; and reproducing the caption data and displaying the reproduced caption data as a 3D caption on the video screen based on the determined reproducing form of the caption data.
According to an aspect of another exemplary embodiment, there is provided an apparatus for generating a broadcasting bitstream for a digital caption broadcast, the apparatus including: a video data receiver for receiving video data in which a video including at least one of a 2D video and a 3D video is encoded by a video encoding processor; a 3D caption converting information determiner for determining caption data for reproduction in conjunction with the video, and 3D caption converting information including information relating to a converting speed of an offset for reproducing the caption data as a 3D caption; and a bitstream output unit for outputting a bitstream for a digital broadcast by multiplexing the received video data, the determined caption data, and the determined 3D caption converting information.
According to an aspect of another exemplary embodiment, there is provided an apparatus for receiving a broadcasting bitstream for a digital caption broadcast, the apparatus including: a bitstream receiver for receiving a bitstream including encoded video data which includes at least one of a 2-dimensional (2D) video and a 3D video; an extractor for extracting the encoded video data, caption data for reproduction in conjunction with a video, and 3D caption converting information including information relating to a converting speed of an offset for reproducing the caption data as a 3D caption from the bitstream by de-multiplexing and parsing the received bitstream; and a caption determiner for determining a reproducing form of the caption data relating to displaying the reproduced caption data as a 3D caption on a video screen, based on the extracted 3D caption converting information.
The apparatus may further include: a video reconstructor which reconstructs at least one video from among the 2D video and the 3D video by decoding the encoded video data by interlocking with a video decoding processor; and a reproducer which reproduces the caption data as a 3D caption and displays the 3D caption on the video screen based on the determined reproducing form of the caption data.
According to an aspect of another exemplary embodiment, there is provided non-transitory computer-readable recording medium having recorded thereon program for executing the methods for generating a digital broadcasting bitstream by using an operation processor.
According to a digital broadcasting bitstream generated according to at least one exemplary embodiment, 3D caption converting information, 3D caption offset information, caption offset converting speed information, 3D caption size converting information, and 3D caption transport information according to an exemplary embodiment may be transmitted and received by using at least one of a service block of a bitstream, a caption window command, and a space in a section table region.
Further, a 3D broadcast program having a visually natural appearance to a television (TV) viewer may be provided because a 2D caption reproducing state and a 3D caption reproducing state are prevented from being rapidly changed, a caption size may be changed in proportion to a change of a caption depth, and a reproduction order may be set by assigning a 3D caption priority between a plurality of caption windows that overlap each other.